The effect of Cinnamaldehyde on mucositis and salivary antioxidant capacity in gamma-irradiated rats (a preliminary study)

Abstract
Background and purpose of the study The aim of this study was to investigate the effect of cinnamaldehyde on mucositis and salivary total antioxidant capacity in gamma-irradiated rats. Methods The study was conducted on 28 male Wistar rats, 7–11 weeks of age and 160 ± 20 g body weight, divided into four groups of seven rats each. The first group receiving normal saline (S), the second group receiving saline and gamma radiation (SR), the third group receiving 50 mg/kg cinnamaldehyde 98% (C), and the fourth group receiving 50 mg/kg cinnamaldehyde 98% and gamma radiation (CR). SR and CR groups were exposed to 15 Gy gamma irradiation for 7 min and 39 s. Rats were intraperitoneally injected each day during the 10-day period of the experiment, and their tongues and lips were examined to assess the incidence and severity of mucositis. The saliva samples were taken from the animals three times on day zero, six, and ten. Results The mean mucositis incidence appeared to be delayed in the CR than the SR group (P = 0.024), and the severity was significantly higher in the SR compared to the CR group;the difference was statistically significant on the second day (P = 0.027). In the evaluation of salivary antioxidant capacity, salivary antioxidant concentration was significantly higher in the C than the S, SR, and CR groups on the tenth day of the experiment (p <0.05). Conclusion The clinical effects in the CR group seem to be due to antioxidant, anti-bacterial and anti-inflammatory effects of cinnamaldehyde; this conclusion, however, requires further investigations. Delayed antioxidant effect in the CR group was evident in ip cinnamaldehyde injection, the exact mechanism is not clear.